Re: [PATCH 2/2] i2c: Dynamically assign adapter id if it wasn'texplictly specified

From: Karol Lewandowski
Date: Thu Mar 22 2012 - 11:29:09 EST


On 16.03.2012 13:19, Karol Lewandowski wrote:

>> Commit 488bf314b ("i2c: Allow i2c_add_numbered_adapter() to assign a
>> bus id") reworked i2c_add_numbered_adapter() to call i2c_add_adapter()
>> if requested bus was -1.

>> This allows to simplify driver's initialization procedure as it allows

>> static and dynamic adapter id registration using one function.
>>
>> This patch updates few more drivers (missed out in original patch) to
>> use this functionality.
>

> [ I must have lost actual problem description while rewording
> message itself... ]
>
> Problem arises when multiple drivers (or multiple instances
> of one driver) try to assume the same fixed bus number (0).
>
> This simply causes i2c_add_numbered_bus() to fail.
> Leaving -1 works perfectly, as registration function switches
> to dynamic id registration.

>> Signed-off-by: Karol Lewandowski <k.lewandowsk@xxxxxxxxxxx>
>> Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
>> ---
>> drivers/i2c/busses/i2c-gpio.c | 7 +------
>> drivers/i2c/busses/i2c-octeon.c | 2 +-
>> drivers/i2c/busses/i2c-pca-platform.c | 2 +-
>> drivers/i2c/busses/i2c-versatile.c | 9 ++-------
>> 4 files changed, 5 insertions(+), 15 deletions(-)


Dear Haavard, Rade, Wolfram and Russel

Could you review following changes for gpio, octeon, pca-platform
and versatile i2c controller drivers (for which you are, or were,
maintainers)?

Grant requested explicit Ack to get this merged.

Thanks!

>
> diff --git a/drivers/i2c/busses/i2c-gpio.c b/drivers/i2c/busses/i2c-gpio.c
> index a651779..50a2a94 100644
> --- a/drivers/i2c/busses/i2c-gpio.c
> +++ b/drivers/i2c/busses/i2c-gpio.c
> @@ -144,12 +144,7 @@ static int __devinit i2c_gpio_probe(struct platform_device *pdev)
> adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
> adap->dev.parent = &pdev->dev;
>
> - /*
> - * If "dev->id" is negative we consider it as zero.
> - * The reason to do so is to avoid sysfs names that only make
> - * sense when there are multiple adapters.
> - */
> - adap->nr = (pdev->id != -1) ? pdev->id : 0;
> + adap->nr = pdev->id;
> ret = i2c_bit_add_numbered_bus(adap);
> if (ret)
> goto err_add_bus;
> diff --git a/drivers/i2c/busses/i2c-octeon.c b/drivers/i2c/busses/i2c-octeon.c
> index ee139a5..8470232 100644
> --- a/drivers/i2c/busses/i2c-octeon.c
> +++ b/drivers/i2c/busses/i2c-octeon.c
> @@ -581,7 +581,7 @@ static int __devinit octeon_i2c_probe(struct platform_device *pdev)
>
> i2c->adap = octeon_i2c_ops;
> i2c->adap.dev.parent = &pdev->dev;
> - i2c->adap.nr = pdev->id >= 0 ? pdev->id : 0;
> + i2c->adap.nr = pdev->id;
> i2c_set_adapdata(&i2c->adap, i2c);
> platform_set_drvdata(pdev, i2c);
>
> diff --git a/drivers/i2c/busses/i2c-pca-platform.c b/drivers/i2c/busses/i2c-pca-platform.c
> index 2adbf1a..675878f 100644
> --- a/drivers/i2c/busses/i2c-pca-platform.c
> +++ b/drivers/i2c/busses/i2c-pca-platform.c
> @@ -171,7 +171,7 @@ static int __devinit i2c_pca_pf_probe(struct platform_device *pdev)
> i2c->io_size = resource_size(res);
> i2c->irq = irq;
>
> - i2c->adap.nr = pdev->id >= 0 ? pdev->id : 0;
> + i2c->adap.nr = pdev->id;
> i2c->adap.owner = THIS_MODULE;
> snprintf(i2c->adap.name, sizeof(i2c->adap.name),
> "PCA9564/PCA9665 at 0x%08lx",
> diff --git a/drivers/i2c/busses/i2c-versatile.c b/drivers/i2c/busses/i2c-versatile.c
> index 6055601..9458568 100644
> --- a/drivers/i2c/busses/i2c-versatile.c
> +++ b/drivers/i2c/busses/i2c-versatile.c
> @@ -102,13 +102,8 @@ static int i2c_versatile_probe(struct platform_device *dev)
> i2c->algo = i2c_versatile_algo;
> i2c->algo.data = i2c;
>
> - if (dev->id >= 0) {
> - /* static bus numbering */
> - i2c->adap.nr = dev->id;
> - ret = i2c_bit_add_numbered_bus(&i2c->adap);
> - } else
> - /* dynamic bus numbering */
> - ret = i2c_bit_add_bus(&i2c->adap);
> + i2c->adap.nr = dev->id;
> + ret = i2c_bit_add_numbered_bus(&i2c->adap);
> if (ret >= 0) {
> platform_set_drvdata(dev, i2c);
> return 0;



--
Karol Lewandowski | Samsung Poland R&D Center | Linux/Platform
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/